Going blue in the face over black

April 17, 2008 8:07 AM

How to make InDesign export colours properly?

I have an InDesign document, and on the master I have made a rectangle the size of the page, in black.

Whenever I export to PDF, this black rectangle turns grey.

I've dealt with the before, I just can't remember how - I've tried turning all image compression off, but it doesn't seem to be doing the trick.

Any help appreciated!

posted by djgh to computers & internet (20 comments total)

Google sez:

Check for:

Preferences/Appearance of Black: Printing/Exporting: Output all Blacks Accurately.

Not that I know anything about InDesign, but why can't it do that anyway?
posted by Magnakai at 8:30 AM on April 17

Not that I know anything about InDesign, but why can't it do that anyway?

That setting makes it output all blacks as their exact cmyk values. Often in printing you add other inks into black to increase its intensity.

djgh -- what are the cmyk values of your black?
posted by nathan_teske at 8:36 AM on April 17

And oh is the black actually shifting values to gray or is it just rendering as gray?
posted by nathan_teske at 8:39 AM on April 17

Output as Rich Black doesn't seem to be working.

nathan_teske: 0 0 0 100
posted by djgh at 8:43 AM on April 17

And oh is the black actually shifting values to gray or is it just rendering as gray?

Not entirely sure how to find that one out...
posted by djgh at 8:43 AM on April 17

nathan_teske refers to rich black. On Typophile, some people recommend some different compositions of rich black. You could experiment with that.
posted by kidbritish at 8:45 AM on April 17

Check the Destination of your PDF in the Output section of the PDF Export dialog box. You could have some funky color conversion thing in there. Or it could just be your PDF viewer doing a poor job at converting CMYK black to RGB black for display. If this PDF is for screen only, set your destination to one of the RGBs and you should see an improvement.
posted by wemayfreeze at 8:45 AM on April 17

Rich black should only matter for CMYK output. The problem here is the CMYK -> RGB color conversion (necessary for display on a monitor). You can replicate the problem (or, a problem anyhow!) by making a black (0 0 0 100K) box in InDesign, selecting it, and changing the color mode to RGB in the color pallet (using the fly-out menu). It returns 35R 31G 32B on my computer, and renders as a dark grey.
posted by wemayfreeze at 8:48 AM on April 17

wemayfreeze - Eventual destination is printing. Will it therefore print fine as is when I send it to the printers as a PDF?
posted by djgh at 8:54 AM on April 17

0c 0m 0y 100k is not a good black for printing four-color process. Try 30c 30m 30y 100k or some other variant. And the only way to know for sure how it will look is to view the proofs yourself (printed from the same equipment as the final output).
posted by kidbritish at 9:00 AM on April 17

Yeah. If your colors are all CMYK then the PDF will print properly. Leave the Destination option alone (No Color Conversion).

If you're still worried, ask the printer to confirm that the blacks are correct in the PDF. If you have large fields of black you'll want to use a rich black. Different printers like different mixes—ask them about that, too. If this is some kind of online deal without easy access to actual people, make it something like 60 40 30 100—it's what we use where I work.
posted by wemayfreeze at 9:04 AM on April 17

If this is going on newsprint, your rich black should be 40c 0m 0y 100K. We have problems with people turning in PDFs with 4 color rich black. On a news press, with 100 line screen printing and horrible dot gain, it will reproduce poorly. However, if it's going on better stock, then a 40c 30m 30y 100K black is a good idea. Straight 0-0-0-100 should be used for very small text (below 8 pt.) These are only genreal recommendations - if you have any questions, it is imperative that you call your print shop. They will tell you exactly what they need from you. Each shop is different and they'll appreciate you calling to get things right, instead of them fighting with your file to get it to output.
posted by azpenguin at 9:10 AM on April 17

I had banners printed that were primarily black as a campaign for PlayStation. They were c50 m50 y50 k100. That is rich black. Out of curiosity are you using a PC or a Mac? When you are previewing the PDF that you have exported are you using Adobe Acrobat, or Preview or something else? That might help.
posted by stackhaus23 at 10:01 AM on April 17

Before you go playing around with the CMYK values for your black area, please talk to your printer. Different presses and papers have different tolerances. For example, if a client was to give me a file with a rich black of 50, 50, 50, 100 I would have to modify that to 35, 35, 35, 100 because the former values cold very possibly make the paper fall apart. Ink is wet, and too much ink will turn paper to pulp.

Now, when you say the black rectangle turns gray, do you mean on-screen, off an desktop inkjet, or on your printer's proof? 'Cause they can mean three different things.
posted by lekvar at 10:23 AM on April 17 [1 favorite]

I just tested it and the default export works fine, with a 100k rectangle. Are you sure your shape doesn't have a blending effect or opacity applied?
posted by TochterAusElysium at 12:23 PM on April 17

Answers to various questions:

- I'm on a Mac
- It's gone grey when I view the exported PDF in Preview
- There's no blending or opacity

And default High Quality Print suffers from the same problem as my modified, no compression on anything version.

Changing the output to some RGB (I forget which) solved the problem for the PDF, but I'm worried that it will look weird when printed. I guess I'll have to talk to the printer about it, but it's weird because I had exactly the same issue ages ago and managed to solve it (or the printers adjusted to black without telling me).
posted by djgh at 4:19 PM on April 17

Preview is really bad at displaying colors correctly. If you have either Illustrator or Acrobat you can open the PDF and use the Eyedropper (Illustrator) or the Print Production tools (Acrobat) to determine what the value of the true color.
posted by lekvar at 4:40 PM on April 17

If you don't have either of those programs, send the file to your printer and ask them what the ink value is. Chances are if it's 100% in InDesign it'll be 100% on-press.
posted by lekvar at 4:41 PM on April 17

Changing the output to some RGB (I forget which) solved the problem for the PDF, but I'm worried that it will look weird when printed.

It will. Don't do this. Use that PDF only for screen display, not for final output.

If this piece is intended for print only, I really don't think you have a problem here. 0 0 0 100 often displays weirdly when converted to RGB. You said you had this problem before and managed to fix it. Maybe you used a rich black mix? RGB display of rich black tends to end up lots more black than reg'lar ol' black.

Also, when you say "the printers adjusted to black without telling" you, do you mean they fixed your PDF? Or do you mean it printed fine? 'Cause if it printed fine, then that's more evidence that you'll be OK with the PDF you have.
posted by wemayfreeze at 5:35 PM on April 17

The last time, it ended up printed fine. But it also displayed fine in Preview.

So either Preview reflected the final printed output correctly, and all was well;
Or, Preview didn't reflect the output, which the printer corrected in the PDF.

Either way, I guess I'll just have to speak to the printers...

Thanks for everybody's help!
posted by djgh at 5:30 AM on April 18